Physali is the unofficial capital of the merperson world. They do have a ruler, known as the Sea King, but he is not a part of the Authoritative Council; he simply keeps order among the world of merpeople. Physali is a pretty city of ruins, rumored to have once been a part of land, for there is no way the stone buildings could've been made underwater.
An immense coral reef surrounding Physali, the Vatra Reef is a colorful additive to the merpeople's underwater society. It is home to thousands of organisms and beautiful sea creatures, and it bordered by the stinging fire coral that warns others to back off.
Unnamed, the generic kelp forest of the Vatra Sea is thick with vegetation and actually quite beautiful. Seagrass beds are found on the bottom while the kelp lies idly like trees in a surface forest, swaying involuntarily with the gentle current of the ocean.
Though not an official province, the Vatra Sea is incredibly important to Hegatzi for one reason: merpeople. They've created their own metropolis below the surface of the Vatra Sea, complete with its own city, coral reef, and seagrass beds. There are also islands near the Achomawi River Delta that are almost exclusively used by the race of aquatic humans.